This invention relates to check valves, and also to a check valve which is useful for controlling fluid flow to and from a high pressure reciprocating pump.
The rate at which hydrocarbon wells and the like can be drilled can be greatly increased by increasing the pressure of the mud-water drilling fluid which is pumped down the drill string to the drill bit. Although greatly increased drill rates can be achieved by increasing the drilling mud pressure from a typical pressure such as 3,000 psi to a high pressure such as 15,000 psi, it is found that the pumping equipment has a much shorter lifetime, particularly for the pump and its valves. My earlier patent application Ser. No. 774,229 filed Mar. 4, 1977, describes a reciprocating mud pump for producing high pressures, which pumps a large volume with each stroke to minimize the number of times the valves must open and close, to thereby increase the valve life. Additional steps which could increase the life of the valves would make the utilization of high drilling fluid pressures more economical.